Process for preparing an oil containing one or more long-chain polyunsaturated fatty acids derived from biomass; foodstuff or nutritional, cosmetic or pharmaceutical composition containing it

Abstract

A stable oil containing LC-PUFAs in the form of triacylglycerols, in particular arachidonic acid (ARA), dihomogammalinolenic acid (DHGLA), docosahexaenoic acid (DHA) or eicosapentaenoic acid (EPA), may be prepared by direct pressing of one or more biomasses obtained from the culture of a microorganism, especially of a fungus or of a microalga containing the acids ARA, DHGLA, DHA or EPA leading to a first press oil and by bringing a carrier oil entering into the composition of a foodstuff, a cosmetic or pharmaceutical product, into contact with the biomass cake, followed by pressing leading to a second press oil, and then by combining the pressed oils and refining the mixture under controlled conditions.

1. A process for preparing a stable oil containing long-chain polyunsaturated fatty acids in the form of triacylglycerols, the process comprising:
 compressing at least one biomass obtained from the culture of a microorganism in a dry state so as to obtain a first pressed oil and a pressed cake; 
 treating the first pressed oil thus obtained with an adsorbent; 
 subjecting the first pressed oil to deodorization under controlled conditions; 
 bringing a carrier oil into contact with the pressed cake of the biomass so as to form a mixture and transfer long-chain polyunsaturated fatty acid(s) in the form of triacylglycerols to the carrier oil; and 
 pressing the mixture to obtain a second pressed oil. 
 
     
     
       2. A process according to  claim 1 , wherein the biomass contains at least one long-chain polyunsaturated fatty acid chosen from the group consisting of arachidonic acid and docosahexanenoic acid. 
     
     
       3. A process according to  claim 1 , wherein a biomass comprising arachidonic acid is treated. 
     
     
       4. A process according to  claim 1 , wherein a biomass comprising docosahexaenoic is treated. 
     
     
       5. A process according to  claim 1 , wherein a mixture of biomasses, containing arachidonic acid and docosahexaenoic acid is treated. 
     
     
       6. A process according to  claim 1 , wherein the first and second pressed oils are subjected to physical refining using a processing agent. 
     
     
       7. A process according to  claim 6 , wherein the treatment is carried out during contact with the carrier oil or after production of the second pressed oil. 
     
     
       8. A process according to  claim 1 , wherein the walls of the cells of the microorganisms are broken by pressing. 
     
     
       9. A process according to  claim 1 , wherein the pressed cake of the biomass is subjected to grinding in the presence of the carrier oil under gentle conditions, at a moderate temperature under an inert atmosphere. 
     
     
       10. A process according to  claim 1 , comprising the step of carrying out a final filtration in order to remove fine particles of biomass residue. 
     
     
       11. A process according to  claim 1 , wherein the long-chain polyunsaturated fatty acids contained in the stable oil are chosen from the group consisting of arachidonic acid, dihomogammalinolenic acid, docosahexaenoic acid and eicosapentaenoic acid. 
     
     
       12. A process according to  claim 1 , wherein the carrier oil is provided in a composition selected from the group consisting of a food, nutritional, pharmaceutical and a cosmetic product. 
     
     
       13. A process according to  claim 1 , comprising the steps of separating the carrier oil containing the fatty acid from the biomass cake by pressing and filtration to produce the second pressed oil, and combining and refining the first and second pressed oils under controlled conditions. 
     
     
       14. A process according to  claim 1 , comprising the step of subjecting the microorganism to a process that increases the level of incorporation of long-chain polyunsaturated fatty acids in the form of triacylglycerols from the pressed cake of the biomass into the carrier oil. 
     
     
       15. A process according to  claim 1 , wherein the pressed cake of the biomass is subjected to grinding in the presence of the carrier oil under a nitrogen layer.